• Title/Summary/Keyword: Mo-99

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Analysis of Pollutant Transport in Subsurface Materials by Using Radioisotope (동위원소를 이용한 지하매질내 오염물 이동 해석)

  • Kim, Ki Chul;Park, Geon Hyeong;Jung, Sung Hee;Suh, Kyung Suk
    • Journal of Radiation Industry
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    • v.4 no.1
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    • pp.79-83
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    • 2010

  • The pollutants in subsurface soil are advected by groundwater flow and transported by the hydrodynamic dispersion. In this study, laboratory-scale experiments by using a radioisotope were conducted to evaluate the characteristics of the transport and dispersion of pollutants in the soil. The hydraulic model of the laboratory-scale was manufactured based upon its geometric similarity. Tc-99m having a short half-life was used with a tracer and it was injected instantaneously into the soil. Tc-99m milked from a $^{99}Mo/^{99m}Tc$ portable generator fabricated for medical purposes had 0.141 MeV of gamma radiation. The experiments are performed by the different conditions like the variations of groundwater velocity and the results are analyzed by the measured CPS of Tc-99m.

A Study on the Magnetic Separation of Magnetite from Spent Iron-oxide Catalyst (폐 산화철촉매로부터 마그네타이트의 자력선별에 관한 연구)

  • 현종영;이효숙;이우철;채영배
    • Resources Recycling
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    • v.11 no.3
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    • pp.31-36
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    • 2002

  • Magnetic separation was carried out in order to improve the magnetite grade of the spent iron oxide catalyst, that was composed with magnetite, ceria and soluble alkaline salt. The recovery of magnetite from the spent iron oxide catalyst was over 99%, and the magnetite contents was upgraded to about 80% from 70% via wet type magnetic separation at 500 Gauss. This improvement was due to the removal of alkaline salt by water instead of the magnetic separation.

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Precipitation behaviors of Cs and Re(/Tc) by NaTPB and TPPCl from a simulated fission products-$(Na_2CO_3-NaHCO_3)-H_2O_2$ solution (모의 FP-$(Na_2CO_3-NaHCO_3)-H_2O_2$ 용액으로부터 NaTPB 및 TPPCl에 의한 Cs 및 Re(/Tc)의 침전 거동)

  • Lee, Eil-Hee;Lim, Jae-Gwan;Chung, Dong-Yong;Yang, Han-Beum;Kim, Kwang-Wook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.2
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    • pp.115-122
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    • 2010

  • In this study, the removal of Cs and Tc from a simulated fission products (FP) solution which were co-dissolved with U during the oxidative-dissolution of spent fuel in a mixed carbonate solution of $(Na_2CO_3-NaHCO_3)-H_2O_2$ was investigated by using a selective precipitation method. As Cs and Tc might cause an unstable behavior due to the high decay heat emission of Cs as well as the fast migration of Tc when disposed of underground, it is one of the important issues to removal them in views of the increase of disposal safety. The precipitation of Cs and Re (as a surrogate for Tc) was examined by introducing sodium tetraphenylborate (NaTPB) and tetraphenylphosponium chloride (TPPCl), respectively. Precipitation of Cs by NaTPB and that of Re by TPPCl were completed within 5 minutes. Their precipitation rates were not influenced so much by the temperature and stirring speed even if they were increased by up to $50^{\circ}C$ and 1,000 rpm. However, the pH of the solution was found to have a great influence on the precipitation with NaTPB and TPPCl. Since Mo tends to co-precipitate with Re at a lower pH, especially, it was effective that a selective precipitation of Re by TPPCl was carried out at pH of above 9 without co-precipitation of Mo and Re. Over 99% of Cs was precipitated when the ratio of [NaTPB]/[Cs]>1 and more than 99% of Re, likewise, was precipitated when the ratio of [TPPCl]/[Re]>1.

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